| 1 | ; $Id: iccio.asm,v 1.3 1999-06-10 20:47:59 phaller Exp $
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| 2 |
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| 3 | ; **********************************************************************
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| 4 | ; Copyright (C) 1995 by Holger Veit (Holger.Veit@gmd.de)
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| 5 | ; Use at your own risk! No Warranty! The author is not responsible for
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| 6 | ; any damage or loss of data caused by proper or improper use of this
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| 7 | ; device driver.
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| 8 | ; **********************************************************************
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| 9 | ;
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| 10 | ; compile with ALP
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| 11 | ;
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| 12 | TITLE ICCIO.ASM
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| 13 | .386
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| 14 | .387
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| 15 |
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| 16 | DATA32 SEGMENT DWORD PUBLIC USE32 'DATA'
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| 17 | ASSUME CS:FLAT ,DS:FLAT,SS:FLAT
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| 18 | EXTRN ioentry:DWORD
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| 19 | EXTRN gdt:WORD
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| 20 | EXTRN devname:BYTE
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| 21 | DATA32 ENDS
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| 22 |
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| 23 | CODE32 SEGMENT DWORD PUBLIC USE32 'CODE'
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| 24 | ASSUME CS:FLAT ,DS:FLAT,SS:FLAT
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| 25 |
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| 26 | ALIGN 04H
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| 27 |
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| 28 | ; performs fast output of a byte to an I/O port
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| 29 | ; this routine is intended to be called from icc C code
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| 30 | ;
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| 31 | ; Calling convention:
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| 32 | ; void _c_outb(short port,char data)
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| 33 | ;
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| 34 | ;
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| 35 | PUBLIC _c_outb
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| 36 | _c_outb PROC
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| 37 | MOV EDX, DWORD PTR [ESP+4] ; get port
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| 38 | MOV AL, BYTE PTR [ESP+8] ; get data
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| 39 | PUSH EBX ; save register
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| 40 | MOV EBX, 4 ; function code 4 = write byte
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| 41 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 42 | POP EBX
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| 43 | RET
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| 44 | _c_outb ENDP
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| 45 |
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| 46 | ; performs fast output of a word to an I/O port
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| 47 | ; this routine is intended to be called from icc C code
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| 48 | ;
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| 49 | ; Calling convention:
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| 50 | ; void _c_outw(short port,short data)
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| 51 | ;
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| 52 | ;
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| 53 | ALIGN 04H
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| 54 |
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| 55 | PUBLIC _c_outw
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| 56 | _c_outw PROC
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| 57 | MOV EDX, DWORD PTR [ESP+4] ; get port
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| 58 | MOV AX, WORD PTR [ESP+8] ; get data
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| 59 | PUSH EBX ; save register
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| 60 | MOV EBX, 5 ; function code 5 = write word
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| 61 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 62 | POP EBX
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| 63 | RET
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| 64 | _c_outw ENDP
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| 65 |
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| 66 | ; performs fast output of a dword to an I/O port
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| 67 | ; this routine is intended to be called from icc C code
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| 68 | ;
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| 69 | ; Calling convention:
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| 70 | ; void _c_outl(short port,long data)
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| 71 | ;
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| 72 | ;
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| 73 | ALIGN 04H
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| 74 |
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| 75 | PUBLIC _c_outl
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| 76 | _c_outl PROC
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| 77 | MOV EDX, DWORD PTR [ESP+4] ; get port
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| 78 | MOV EAX, DWORD PTR [ESP+8] ; get data
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| 79 | PUSH EBX ; save register
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| 80 | MOV EBX, 6 ; function code 6 = write dword
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| 81 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 82 | POP EBX
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| 83 | RET
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| 84 | _c_outl ENDP
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| 85 |
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| 86 | ; performs fast input of a byte from an I/O port
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| 87 | ; this routine is intended to be called from gcc C code
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| 88 | ;
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| 89 | ; Calling convention:
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| 90 | ; char _c_inb(short port)
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| 91 | ;
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| 92 | ;
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| 93 | ALIGN 04H
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| 94 | PUBLIC _c_inb
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| 95 | _c_inb PROC
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| 96 | MOV EDX, DWORD PTR [ESP+4] ; get port number
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| 97 | PUSH EBX ; save register
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| 98 | MOV EBX, 1 ; function code 1 = read byte
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| 99 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 100 | AND EAX, 000000ffH ; mask out required byte
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| 101 | POP EBX ; restore register
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| 102 | RET
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| 103 | _c_inb ENDP
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| 104 |
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| 105 | ; performs fast input of a word from an I/O port
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| 106 | ; this routine is intended to be called from gcc C code
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| 107 | ;
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| 108 | ; Calling convention:
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| 109 | ; short _c_inw(short port)
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| 110 | ;
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| 111 | ;
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| 112 | ALIGN 04H
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| 113 | PUBLIC _c_inw
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| 114 | _c_inw PROC
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| 115 | MOV EDX, DWORD PTR [ESP+4] ; get port number
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| 116 | PUSH EBX ; save register
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| 117 | MOV EBX, 2 ; function code 2 = read short
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| 118 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 119 | AND EAX, 0000ffffH ; mask out required byte
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| 120 | POP EBX ; restore register
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| 121 | RET
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| 122 | _c_inw ENDP
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| 123 |
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| 124 | ; performs fast input of a dword from an I/O port
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| 125 | ; this routine is intended to be called from gcc C code
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| 126 | ;
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| 127 | ; Calling convention:
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| 128 | ; long _c_inl(short port)
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| 129 | ;
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| 130 | ;
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| 131 | ALIGN 04H
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| 132 | PUBLIC _c_inl
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| 133 | _c_inl PROC
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| 134 | MOV EDX, DWORD PTR [ESP+4] ; get port number
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| 135 | PUSH EBX ; save register
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| 136 | MOV EBX, 3 ; function code 3 = read long
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| 137 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 138 | ; AND EAX, 000000ffH ; mask out required byte
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| 139 | POP EBX ; restore register
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| 140 | RET
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| 141 | _c_inl ENDP
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| 142 |
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| 143 | ALIGN 4
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| 144 | PUBLIC _c_readmsr
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| 145 | _c_readmsr PROC NEAR
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| 146 | PUSH EBP
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| 147 | MOV EBP, ESP
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| 148 | PUSH EAX
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| 149 | PUSH EBX
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| 150 | PUSH ECX
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| 151 | PUSH EDX ; save register
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| 152 | MOV ECX, DWORD PTR [EBP+8] ; get msr reg
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| 153 | MOV EBX, 7 ; function code 7 = read msr
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| 154 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 155 | MOV EBX, DWORD PTR [EBP+12] ; LONGLONG ptr
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| 156 | MOV DWORD PTR [EBX+4], EDX
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| 157 | MOV DWORD PTR [EBX], EAX
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| 158 | POP EDX
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| 159 | POP ECX
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| 160 | POP EBX ; restore register
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| 161 | POP EAX
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| 162 | POP EBP
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| 163 | RET
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| 164 | _c_readmsr ENDP
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| 165 |
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| 166 | ;------------------------------------------------------------------------------
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| 167 |
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| 168 | ; performs fast output of a byte to an I/O port
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| 169 | ; this routine is intended to be called from assembler code
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| 170 | ; note there is no stack frame, however 8 byte stack space is required
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| 171 | ;
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| 172 | ; calling convention:
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| 173 | ; MOV EDX, portnr
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| 174 | ; MOV AL, data
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| 175 | ; CALL a_outb
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| 176 | ;
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| 177 | ;
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| 178 | ALIGN 04H
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| 179 | PUBLIC a_outb
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| 180 | a_outb PROC
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| 181 | PUSH EBX ; save register
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| 182 | MOV EBX, 4 ; function code 4 = write byte
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| 183 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 184 | POP EBX ; restore bx
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| 185 | RET
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| 186 | a_outb ENDP
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| 187 |
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| 188 | ; performs fast output of a word to an I/O port
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| 189 | ; this routine is intended to be called from assembler code
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| 190 | ; note there is no stack frame, however 8 byte stack space is required
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| 191 | ;
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| 192 | ; calling convention:
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| 193 | ; MOV EDX, portnr
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| 194 | ; MOV AX, data
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| 195 | ; CALL a_outw
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| 196 | ;
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| 197 | ;
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| 198 | ALIGN 04H
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| 199 | PUBLIC a_outw
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| 200 | a_outw PROC
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| 201 | PUSH EBX ; save register
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| 202 | MOV EBX, 5 ; function code 5 = write word
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| 203 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 204 | POP EBX ; restore bx
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| 205 | RET
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| 206 | a_outw ENDP
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| 207 |
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| 208 | ; performs fast output of a long to an I/O port
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| 209 | ; this routine is intended to be called from assembler code
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| 210 | ; note there is no stack frame, however 8 byte stack space is required
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| 211 | ;
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| 212 | ; calling convention:
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| 213 | ; MOV EDX, portnr
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| 214 | ; MOV EAX, data
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| 215 | ; CALL a_outl
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| 216 | ;
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| 217 | ;
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| 218 | ALIGN 04H
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| 219 | PUBLIC a_outl
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| 220 | a_outl PROC
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| 221 | PUSH EBX ; save register
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| 222 | MOV EBX, 6 ; function code 6 = write long
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| 223 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 224 | POP EBX ; restore bx
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| 225 | RET
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| 226 | a_outl ENDP
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| 227 |
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| 228 | ; performs fast input of a byte from an I/O port
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| 229 | ; this routine is intended to be called from assembler code
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| 230 | ; note there is no stack frame, however 8 byte stack space is required
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| 231 | ;
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| 232 | ; calling convention:
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| 233 | ; MOV EDX, portnr
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| 234 | ; CALL a_inb
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| 235 | ; ;data in AL
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| 236 | ;
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| 237 | ALIGN 04H
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| 238 | PUBLIC a_inb
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| 239 | a_inb PROC
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| 240 | PUSH EBX ; save register
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| 241 | MOV EBX, 1 ; function code 1 = read byte
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| 242 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 243 | AND EAX, 000000FFh ; mask byte
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| 244 | POP EBX ; restore register
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| 245 | RET
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| 246 | a_inb ENDP
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| 247 |
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| 248 |
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| 249 | ; performs fast input of a word from an I/O port
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| 250 | ; this routine is intended to be called from assembler code
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| 251 | ; note there is no stack frame, however 8 byte stack space is required
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| 252 | ;
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| 253 | ; calling convention:
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| 254 | ; MOV EDX, portnr
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| 255 | ; CALL a_inb
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| 256 | ; ;data in AX
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| 257 | ;
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| 258 | ALIGN 04H
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| 259 | PUBLIC a_inw
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| 260 | a_inw PROC
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| 261 | PUSH EBX ; save register
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| 262 | MOV EBX, 2 ; function code 2 = read word
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| 263 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 264 | AND EAX, 0000FFFFh ; mask byte
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| 265 | POP EBX ; restore register
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| 266 | RET
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| 267 | a_inw ENDP
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| 268 |
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| 269 | ; performs fast input of a dword from an I/O port
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| 270 | ; this routine is intended to be called from assembler code
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| 271 | ; note there is no stack frame, however 8 byte stack space is required
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| 272 | ;
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| 273 | ; calling convention:
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| 274 | ; MOV EDX, portnr
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| 275 | ; CALL a_inl
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| 276 | ; ;data in EAX
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| 277 | ;
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| 278 | ALIGN 04H
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| 279 | PUBLIC a_inl
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| 280 | a_inl PROC
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| 281 | PUSH EBX ; save register
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| 282 | MOV EBX, 3 ; function code 3 = read dword
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| 283 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
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| 284 | POP EBX ; restore register
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| 285 | RET
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| 286 | a_inl ENDP
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| 287 |
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| 288 | CODE32 ENDS
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| 289 |
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| 290 | ;------------------------------------------------------------------------------
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| 291 |
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| 292 | ; Initialize I/O access via the driver.
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| 293 | ; You *must* call this routine once for each executable that wants to do
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| 294 | ; I/O.
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| 295 | ;
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| 296 | ; The routine is mainly equivalent to a C routine performing the
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| 297 | ; following (but no need to add another file):
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| 298 | ; DosOpen("/dev/fastio$", read, nonexclusive)
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| 299 | ; DosDevIOCtl(device, XFREE86_IO, IO_GETSEL32)
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| 300 | ; selector -> ioentry+4
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| 301 | ; DosClose(device)
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| 302 | ;
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| 303 | ; Calling convention:
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| 304 | ; int io_init(void)
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| 305 | ; Return:
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| 306 | ; 0 if successful
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| 307 | ; standard APIRET return code if error
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| 308 | ;
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| 309 |
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| 310 | CODE32 SEGMENT
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| 311 | PUBLIC _io_init
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| 312 | EXTRN DosOpen:PROC
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| 313 | EXTRN DosClose:PROC
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| 314 | EXTRN DosDevIOCtl:PROC
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| 315 | _io_init PROC
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| 316 | PUSH EBP
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| 317 | MOV EBP, ESP ; standard stack frame
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| 318 | SUB ESP, 16 ; reserve memory
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| 319 | ; -16 = len arg of DosDevIOCtl
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| 320 | ; -12 = action arg of DosOpen
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| 321 | ; -8 = fd arg of DosOpen
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| 322 | ; -2 = short GDT selector arg
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| 323 | PUSH 0 ; (PEAOP2)NULL
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| 324 | PUSH 66 ; OPEN_ACCESS_READWRITE|OPEN_SHARE_DENYNONE
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| 325 | PUSH 1 ; FILE_OPEN
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| 326 | PUSH 0 ; FILE_NORMAL
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| 327 | PUSH 0 ; initial size
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| 328 | LEA EAX, [EBP-12] ; Adress of 'action' arg
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| 329 | PUSH EAX
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| 330 | LEA EAX, [EBP-8] ; Address of 'fd' arg
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| 331 | PUSH EAX
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| 332 | PUSH OFFSET devname
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| 333 | CALL DosOpen ; call DosOpen
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| 334 | ADD ESP, 32 ; cleanup stack frame
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| 335 | CMP EAX, 0 ; is return code zero?
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| 336 | JE goon ; yes, proceed
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| 337 | LEAVE ; no return error
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| 338 | RET
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| 339 |
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| 340 | ALIGN 04H
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| 341 | goon:
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| 342 | LEA EAX, [EBP-16] ; address of 'len' arg of DosDevIOCtl
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| 343 | PUSH EAX
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| 344 | PUSH 2 ; sizeof(short)
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| 345 | LEA EAX, [EBP-2] ; address to return the GDT selector
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| 346 | PUSH EAX
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| 347 | PUSH 0 ; no parameter len
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| 348 | PUSH 0 ; no parameter size
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| 349 | PUSH 0 ; no parameter address
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| 350 | PUSH 100 ; function code IO_GETSEL32
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| 351 | PUSH 118 ; category code XFREE6_IO
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| 352 | MOV EAX, [EBP-8] ; file handle
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| 353 | PUSH EAX
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| 354 | CALL DosDevIOCtl ; perform ioctl
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| 355 | ADD ESP, 36 ; cleanup stack
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| 356 | CMP EAX, 0 ; is return code = 0?
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| 357 | JE ok ; yes, proceed
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| 358 | PUSH EAX ; was error, save error code
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| 359 | MOV EAX, [EBP-8] ; file handle
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| 360 | PUSH EAX
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| 361 | CALL DosClose ; close device
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| 362 | ADD ESP, 4 ; clean stack
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| 363 | POP EAX ; get error code
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| 364 | LEAVE ; return error
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| 365 | RET
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| 366 |
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| 367 | ALIGN 04H
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| 368 | ok:
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| 369 | MOV EAX,[EBP-8] ; file handle
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| 370 | PUSH EAX ; do normal close
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| 371 | CALL DosClose
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| 372 | ADD ESP, 4 ; clean stack
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| 373 |
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| 374 | MOV AX, WORD PTR [EBP-2] ; load gdt selector
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| 375 | MOV gdt, AX ; store in ioentry address selector part
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| 376 | XOR EAX, EAX ; eax = 0
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| 377 | MOV DWORD PTR [ioentry], EAX ; clear ioentry offset part
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| 378 | ; return code = 0 (in %eax)
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| 379 | LEAVE ; clean stack frame
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| 380 | RET ; exit
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| 381 | _io_init ENDP
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| 382 |
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| 383 | ; just for symmetry, does nothing
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| 384 |
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| 385 | ALIGN 04H
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| 386 | PUBLIC _io_exit
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| 387 | _io_exit PROC
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| 388 | XOR EAX,EAX
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| 389 | RET
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| 390 | _io_exit ENDP
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| 391 |
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| 392 | ALIGN 04H
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| 393 | PUBLIC int03
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| 394 |
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| 395 | int03 PROC
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| 396 | INT 3
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| 397 | RET
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| 398 | int03 ENDP
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| 399 |
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| 400 | ;------------------------------------------------------------------------------
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| 401 |
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| 402 | ; Initialize I/O access via the driver.
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| 403 | ; You *must* call this routine once for each *thread* that wants to do
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| 404 | ; I/O.
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| 405 | ;
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| 406 | ; The routine is mainly equivalent to a C routine performing the
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| 407 | ; following (but no need to add another file):
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| 408 | ; DosOpen("/dev/fastio$", read, nonexclusive)
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| 409 | ; DosDevIOCtl(device, XFREE86IO, IOGETSEL32)
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| 410 | ; selector -> ioentry+4
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| 411 | ; DosClose(device)
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| 412 | ;
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| 413 | ; Calling convention:
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| 414 | ; int io_init1(void)
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| 415 | ; Return:
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| 416 | ; 0 if successful
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| 417 | ; standard APIRET RETurn code if error
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| 418 | ;
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| 419 |
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| 420 | PUBLIC _io_init1
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| 421 | ALIGN 04H
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| 422 | _io_init1 PROC
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| 423 | PUSH EBP
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| 424 | MOV EBP, ESP ; standard stack frame
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| 425 | SUB ESP, 16 ; reserve memory
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| 426 | ; -16 = len arg of DosDevIOCtl
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| 427 | ; -12 = action arg of DosOpen
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| 428 | ; -8 = fd arg of DosOpen
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| 429 | ; -2 = short GDT selector arg
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| 430 | PUSH 0 ; (PEAOP2)NULL
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| 431 | PUSH 66 ; OPENACCESSREADWRITE|OPENSHAREDENYNONE
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| 432 | PUSH 1 ; FILEOPEN
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| 433 | PUSH 0 ; FILENORMAL
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| 434 | PUSH 0 ; initial size
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| 435 | LEA EAX, [EBP-12] ; Adress of 'action' arg
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| 436 | PUSH EAX
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|---|
| 437 | LEA EAX, [EBP-8] ; Address of 'fd' arg
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| 438 | PUSH EAX
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| 439 | PUSH OFFSET devname
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| 440 | CALL DosOpen ; call DosOpen
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| 441 | ADD ESP, 32 ; cleanup stack frame
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| 442 | CMP EAX, 0 ; is return code zero?
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| 443 | JE goon1 ; yes, proceed
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| 444 | LEAVE ; no RETurn error
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| 445 | RET
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| 446 | ALIGN 04H
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| 447 | goon1:
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| 448 | LEA EAX, [EBP-16] ; address of 'len' arg of DosDevIOCtl
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|---|
| 449 | PUSH EAX
|
|---|
| 450 | PUSH 2 ; sizeof(short)
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|---|
| 451 | LEA EAX, [EBP-2] ; address to return the GDT selector
|
|---|
| 452 | PUSH EAX
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|---|
| 453 | PUSH 0 ; no parameter len
|
|---|
| 454 | PUSH 0 ; no parameter size
|
|---|
| 455 | PUSH 0 ; no parameter address
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|---|
| 456 | PUSH 100 ; function code IOGETSEL32
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|---|
| 457 | PUSH 118 ; category code XFREE6IO
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|---|
| 458 | MOV EAX,[EBP-8] ; file handle
|
|---|
| 459 | PUSH EAX
|
|---|
| 460 | CALL DosDevIOCtl ; perform ioctl
|
|---|
| 461 | ADD ESP, 36 ; cleanup stack
|
|---|
| 462 | CMP EAX, 0 ; is return code = 0?
|
|---|
| 463 | JE ok1 ; yes, proceed
|
|---|
| 464 | PUSH EAX ; was error, save error code
|
|---|
| 465 | MOV EAX, [EBP-8] ; file handle
|
|---|
| 466 | PUSH EAX
|
|---|
| 467 | CALL DosClose ; close device
|
|---|
| 468 | ADD ESP,4 ; clean stack
|
|---|
| 469 | POP EAX ; get error code
|
|---|
| 470 | LEAVE ; return error
|
|---|
| 471 | RET
|
|---|
| 472 |
|
|---|
| 473 | ALIGN 04H
|
|---|
| 474 | ok1:
|
|---|
| 475 | MOV EAX, [EBP-8] ; file handle
|
|---|
| 476 | PUSH EAX ; do normal close
|
|---|
| 477 | CALL DosClose
|
|---|
| 478 | ADD ESP,4 ; clean stack
|
|---|
| 479 |
|
|---|
| 480 | MOV AX, [EBP-2] ; load gdt selector
|
|---|
| 481 | MOV gdt, AX ; store in ioentry address selector part
|
|---|
| 482 | XOR EAX, EAX ; EAX = 0
|
|---|
| 483 | MOV DWORD PTR [ioentry], EAX ; clear ioentry offset part
|
|---|
| 484 | ; return code = 0 (in EAX)
|
|---|
| 485 |
|
|---|
| 486 | ; now use this function to raise the IOPL
|
|---|
| 487 | MOV EBX,13 ; special function code
|
|---|
| 488 | CALL FWORD PTR [ioentry] ; CALL intersegment indirect 16:32
|
|---|
| 489 |
|
|---|
| 490 | ; thread should now be running at IOPL=3
|
|---|
| 491 |
|
|---|
| 492 | XOR EAX, EAX ; return code = 0
|
|---|
| 493 | LEAVE ; clean stack frame
|
|---|
| 494 | RET ; exit
|
|---|
| 495 | _io_init1 ENDP
|
|---|
| 496 |
|
|---|
| 497 | PUBLIC _io_exit1
|
|---|
| 498 | ALIGN 04H
|
|---|
| 499 | _io_exit1 PROC
|
|---|
| 500 | push EBP
|
|---|
| 501 | MOV EBP, ESP ; stackframe, I am accustomed to this :-)
|
|---|
| 502 |
|
|---|
| 503 | MOV AX, gdt ; check if ioinit was called once
|
|---|
| 504 | OR AX, AX
|
|---|
| 505 | JZ exerr ; no gdt entry, so process cannot be at IOPL=3
|
|---|
| 506 | ; through this mechanism
|
|---|
| 507 |
|
|---|
| 508 | MOV EBX, 14 ; function code to disable iopl
|
|---|
| 509 | CALL FWORD PTR [ioentry] ; call intersegment indirect 16:32
|
|---|
| 510 |
|
|---|
| 511 | ; process should now be at IOPL=3 again
|
|---|
| 512 | XOR EAX, EAX ; ok, RETurn code = 0
|
|---|
| 513 | LEAVE
|
|---|
| 514 | RET
|
|---|
| 515 | exerr: XOR EAX, EAX ; not ok, RETurn code = ffffffff
|
|---|
| 516 | DEC EAX
|
|---|
| 517 | LEAVE
|
|---|
| 518 | RET
|
|---|
| 519 | _io_exit1 ENDP
|
|---|
| 520 |
|
|---|
| 521 | ; for diagnostic only
|
|---|
| 522 |
|
|---|
| 523 | PUBLIC psw
|
|---|
| 524 | ALIGN 04H
|
|---|
| 525 | psw PROC
|
|---|
| 526 | PUSHF ; get the current PSW
|
|---|
| 527 | POP EAX ; into EAX
|
|---|
| 528 | RET
|
|---|
| 529 | psw ENDP
|
|---|
| 530 |
|
|---|
| 531 | CODE32 ENDS
|
|---|
| 532 | END
|
|---|
